I don't know Ricey, I wasn't into these amps when they were being produced new, so I wasn't around to see how they were sold. My impression is that it was an "option". Mine is just a reverb tank and a controller on top of it. Its laying in the bottom of the head, and the wires just plug into the effects loop. So basically... its nothing more than a spring reverb external pedal, that they screwed into the bottom of the case. It works in a pinch but its pretty crappy really. Better than nothing I guess if you just wanna grab your little head and go. I'll probably never use it though.